Fabric slitting machine



Dec. 12, 1950 R. J. czLARKsoNy FABRIC SLITTING MACHINE 2 Sheets-Sheet 1 Filed Nov. 7, 1947 .ATTORNEY Dec. 12, 1950 R. J. cLARKsoN A2,533,996

FABRIC SLITTING MACHINE Filed Nov. 7, 1947 v 2 sheets-sheet 2 W fr-4 l ZZ fdl?" LD x f/ f77 JL? Patented Dec. 12, 1950 FABRIC SLITTING MACHINE Robert J. Clarkson, Winnsboro, S. C., assignor to United States Rubber Company, New York, N. Y., a corporation of New Jersey Application November 7, 1947, Serial No. 784,623

6 Claims. (Cl. 164-65) This invention relates to a fabric slitting machine and more particularly to` mechanism for guiding a slightly defined row of the fabric to a cutter so that the cutter will slit the-fabric along such row.

Fabric slitting machines are old and well known and as commonly constructed are provided with rotating cutters adapted to slit the fabric between straight rows, such as between straight adjacent threads.

When the rows along which the fabric is to be cut are straight it is a simple matter to cut the fabric at highspeed along such rows, but if the rows are non-straight or wavy as in the specially 'constructed fabric to be described, the problem of slitting the fabric along such nonstraight rows is difficult. y

The slitting machine of the present invention was `developed yprimarily to slit an elastic fabric having a substantial range of stretch and slightly defined rows along the fabric, which rows are wavy or crooked in the unstretched fabric and are therefore difficult tofollow. The rows can be straightened out to a large degree by placing the fabric under high tension but this is objectionable as it tends to set the fabric in its extended condition. It is therefore important to slit this soft stretchable fabric while it is substantiallyfree from tension and the rows where itis to be cutare crooked. If `such a fabric is to be cut at jhigh speed, rather than by hand, it is important to provide specially constructed means capablev of detecting and following a slightly delined crooked row of thefabric.

The present invention contemplates simple and practical means for detecting and following the wavy slightly defined rows of an unstretched fabric and for guiding the rows accurately to the cutters. Such means comprises a flexible detector blade that is adapted to engage and slide along a face of the fabric in a row and of bending readily with bends in the row so as to follow the row and guide it to a cutter.

The above and other features of the present invention will be further understood from the following description when read in connection with the accompanying drawings, wherein:

Fig. 1` is a side View of a fabric slitting machine constructed in accordance with the present invention. T

Fig. 2` is a top plan y view of the machine of` Fig. 4 is aside view with parts in section of manually controlled means for operating a fabric take-up roll.` i

Fig. 5 is a plan view of part ofthe cutting -f rom below the fabric.

Fig. 6 is a view of three of the cutters with the fabric being cut shown in section; and

Fig. 7 is a side view of a flexible detector blade which is adapted to -follow a. slightly defined row of the fabric.

In order to slit fabric in accordance with the present invention it is desirable to provide power operated means for drawing the fabric forward from a source of supply, and to provide power driven rotating cutters for slitting the fabric. The apparatus for drawing the fabric forward from a source of supply past rotating cutters may be variously constructed, and in the embodiment of the invention shown the operating parts are supported by a rectangular frame formed of the uprights I0 which are secured to the longitudinally extending beams II and the transversely extending beams I2. The fabric F to be cut is shown as having been folded back and forth in a supply box I3 so that it may be drawn upwardly out of this box to fabric tensioning rods about which the fabric passes in a tortuous path as shown. The rods I4 are supported by the upright plates I5 carried by the supporting structure I6 attached to the main frame of the slitting machine. The fabric then passes under the free running roll Il supported upon the main frame at I8.

The fabric F `is drawn forward from the apparatus so far described by take-up means, preferably having a take-up rod I9 about which the fabric is wound to form the fabric roll or rolls R. In order to start this winding operation the leading end of the fabric is wrapped by hand two or three turns around the rod I 9 whereupon the ends of this rod are inserted in the guide slots formed in the inclined guides 2l) that extend upwardly in an inclined ddirection from an end portion of the machine frame. The arrangement is such that when this rod I9 with the leading end of the fabric F wound thereuponv is placed in engagement with the slots of the guides 20 it will rest upon a power driven drum 2l mounted upon a supporting shaft 22 that is journaled in brackets secured to the machine frame. This drum 2| is driven by power means, to be described, to rotate the take-up roll R in the direction indicated by the curved arrow shown in Fig. 1.

The cutters for slitting the fabric are disc cutters 23 mounted upon a shaft 24, and since it may be desirable to vary the distance between these cutters so that a fabric may be cut into different width strips, each of these cutters is shown as having an integral hub 25 carrying a set screw 26 which may be tightened to secure the cutter rigidly to the shaft.

The cutter supporting shaft 24 is driven, by means to be described, to rotate the cutters in able, for a purpose'tobe described, to lower the -cutters momentarily as' the fabric is being pulled forward so as toleave a strip across the fabric whichv has not Abeen cut. In order to accomplish this the shaft 24 is rotatably mounted in bearings carried at the upper ends of the rocking arms 21. These arms have their lower ends rigidly secured to a rocking shaft 28 which is journalled in the upright brackets 29. To this through thefabric as shown. It may be desirrocking shaft 28 is rigidly secured a horizontally l extending hand lever 30. The arrangement is such that as long as the machine operator presses downwardly on the lever 30 the cutters 23 will be held in'y the fabric cutting position in which they are shown in Fig. 1, b ut if he pulls up on this lever the cutter supporting arms 21 will swing downwardly and move the cutter` shaft 24 along the arc 3l to disengage the cutters 23 from the fabric.

If the fabric to be cut is an ordinary fabric having straight warp threads it is not diflicult to cut the fabric into straight strips of the desired width, since once the fabric is started running properly each cutter will travel between a pair of straight warps to slit the fabric, but if the fabric to be cut is a soft loosely constructed stretchable fabric in which thewarp threads are in a relaxed and moreor less wavy condition 'the -problem of cutting the'` fabric between selected g pairs of warpsi'smuch moredimcult. 3 'A i While the apparatusof the/present -invention v may be employed to `slit:various fabrics having*y rows that are more or less diflicult to follow, it was developed primarily to cut a loosely woven highly stretchable fabric into Anarrow strips inengagement with the up i 'sheet that rests upon the upper face .of the fabv.ric oversuch guide. Each weight 33 is notched tended for use as stretchable'surgicall bandages.'V

The stretch properties maybe imparted tojsuch fabric by embodying in the fabric the highly stretchable all textile yarns, such as disclosed and claimed in the Foster Patent No. 2,387,320. When a fabric is cut longitudinally into narrow strips, these strips will have raw selvageless edges that will tend to unravel, this tendency however is reduced to a large degree by introducing several leno warp threads in the fabric where it is to be cut so that the fabric may be slit between these leno threads. This will be further understood from Fig. 3 in which is shown a loosely constructed stretchable fabric having the warp threads T, weft threads W and leno threads L. The dot and dash line C indicates where the fabric is to be cut between the slightly spaced sets of leno threads L. The arrangement is such that a slightly defined row is formed at the line C between the leno threads. This row is in fact more difficult to detect and follow in a running fabric F than would appear from an examination of the enlarged view of Fig. 3.

The primary feature of the present invention the row and guide it to the cutter. This is accomplished by providing a flexible detector blade 32 which is best shown in Fig. '7. This blade preferably formed of metal is provided at one end with the flat rounded head 33, it is also provided with a supporting collar 34 located not far from its opposite end 33. The collar 34 is provided with a set screw 36 whereby the detector blade may be rigidly secured to a supporting shaft 3`|l in proper alignment with a cutter 23. The arrangement is such that the detector blades 32 may be adjusted lengthwise of the shaft 31 similar to the manner in which the cutters 23 are adjusted along thezshaft 24, so as to cut fabric lt0 the desired Width. The Shaft 31 is rigidly Slipported bythe machine frame. -The construction of the detector blades is such'that one of these blades is rigidly supported directly in front of each cutter, and extends from its supporting collar 34 towards the approaching fabric far enough to cause the end of the blade which is provided with the head 33 to flex freely laterally. This permits the blade to follow the bends in the wavy row lying between the leno threads L. as best shown in Fig. 5 and straightens the row as it approaches the cutter.

The location of thel detector blades 32 is such that the fabric F travels from the free running roller I1 into engagement with the heads 33 of these blades and the fabric sags slightly between the laterally spaced blades as best shown in Fig. 6. This helps to force the portions of the fabric formed with the slightly defined rows in sliding engagement with the heads 33 of the guides so that each detector blade will follow a row even when the row is non-straight or wavy as shown inFig. 5v.

It is important that th fabric rows be held in r edge of the guides 32 throughout the length guide 32 may be'seen through this' transparent at one end 'as indicated by .33 to clear` the cutter y l23, and has secured to its opposite-end a sup` porting member 40 which may comprise a metal sheet that protrudes beyond the end of the weight and is formed with a looped portion adapted to fit loosely around a supporting rod-4l that extends transversely across the machine frame. The rod 4| serves to hold each weight 33 in position to rest iloatingly upon the portion of the fabric that is sliding along the upper edge of the blade 32,I to thereby maintain the row of the fabric in engagement with such blade so that the row will be guided to a cutter 23.

The cutter shaft 24 is driven, in the construction shown. from an electric motor 42 having the motor shaft 43 that drives the beit 44 which passes around pulleys carried by the shafts 43 and 24. This mechanism serves to drive the cutters 23 at high speeds, and also permits these cutters to be lowered in the manner above described by raising the lever 30 to rock the arms 21. The drum 2| for pulling the fabric F forward and winding iton the rod I9 should operate at a much slower speed than the cutters 23. This drum is therefore driven from the shaft 43 through the reducing belts 45` and 46 that cooperate with the pulleys best shown in Fig. 4. One of these pulleys numbered 41 is rigidly secured to the drum shaft 22, which shaft is rotatably mounted within the drum 2l so that this shaft may be rotated without rotating the drum, the construction being such that the rotation of f the guides, andto facilitate this each guide 32 is provided with a .cooperatingjweight 33 preferably formed of 'av thick piece `of transparent. resinoussheet ma-V terial so that lthe progress 'of the fabric *overa the drum 2l may be stopped without stopping the rotation of the shaft 22.

The construction of the machine shown is preferably such that after the fabric has been introduced into the machine so that its leading end has been firmly attached to the rod I9, and each row of the fabric defined by the slightly spaced leno threads has been engaged with a flexible detector blade 32, the machine is ready to be power operated. The machine operator then starts the electric motor 42 so that it will drive the cutters 23 and rotate the drum shaft 22. He then presses downwardly upon the rocking hand lever 30 to bring the cutters into the fabric slitting position in which they are shown in Fig. 1 and he also steps upon a foot pedal I8 located near the iioor and attached pivotally to` a support at I9. To this foot pedal is connected the pull wire 50 which extends upwardly to a grooved idle roll 5| see Fig. 4, and then laterally to a rocking lever 52 which rocks about the fixed support 53. The upper end of this lever 52 is bifurcated to engage an annular groove 54 formed in the clutch number 55 that is keyed to the power driven shaft 22. The arrangement is such that when the operator steps on the foot treadle 48 to exert a downward pull upon the wire 50 the lever 52 will be pulled in a left hand direction viewing Fig. 4 to force the driving clutch 55 into frictional engagement with the conical end 50 fof the drum 2| and drive this drum. When the machine attendant takes his foot off the treadle 4B so that it can move upwardly to its dotted line position of Fig. 1, the arm 52 will be swung to the right viewing Fig. 4 by the spring 51 to thereby release ,the clutch 55 and tighten a band brake 58 about the drum 2l to stop it from rotation. One end of this band brake 58 is anchored at 59 and the other end is connected by a wire 60 to the rocking arm 52. Should anything go wrong with the fabric slitting operation the operator can quickly stop the winding operation by taking his foot off of the treadle 48, and should he wish to disengage the cutters momentarily from the advancing fabric he can do so by pulling upwardly on the lever 30 to thereby swing the cutters downwardly out of engagement with the fabric.

By employing the slitting mechanism herein described it is possible to slit an elastic or stretchable fabric along previously formed slightly defined rows while the fabric is in a relaxed condition and the rows are crooked, since the detecting means of the present invention is able to follow these crooked rows and guide them to the cutters.

As the fabric is cut into narrow elastic strips theseY are wound upon the rod I9 to form the rolls R, and each strip will have the leno binding threads L at its edges. i

Having thus described my invention, what I claim and desire to protect by Letters Patent is: l. A slitting machine for cutting a stretchable elastic fabric longitudinally along a slightly defined row without stretching the fabric appreciably, which comprises take-up means for drawing the fabric forward from a source of supply, a cutter for cutting the advancing fabric, and means for detecting and following the slightly defined row comprising a flexible detector blade positioned closely adjacent to and in front of the cutter and in alignment therewith and adapted to engage and slide along a face of the fabric in such row and to bend with,bends in the row to follow the row and guide it to the cutter.

2. A slitting machine for cutting a fabric along a slightly defined row, which comprises take-up means for drawing the fabric forward from a source of supply, a cutter for cutting the advancing fabric, means for detecting and following the slightly defined row comprising a flexible detector blade rigidly supported closely adjacent 'to and in front of the cutter in alignment therewith and adapted to engage and slide along a. face of the fabric in such row and to bend readily at its outer end with bends in the row to follow the row and guide it to the cutter.

3. A slitting machine for cutting a fabric along a slightly defined row, which comprises take-up means for drawing the fabric forward from a source of supply, a cutter for cutting the advancing fabric, and means for detecting and following the slightly dened row comprising a. flexible detector blade rigidly supported closely adjacent to and in front of the cutter in alignment therewith and a cooperating pressure plate for holding the blade in the fabric'row to slide therein upon the face of the fabric, and said blade being adapted to bend readily at its outer end to follow bends in the row andv guide the row to the cutter. f

4. A slitting machine for cutting a fabric along a slightly defined row, which comprises take-up means for drawing the fabric forward from a source of supply, a cutter for cutting the advancing fabric. and means for detecting and following a slightly defined row comprising a flexible detector blade rigidly supported closely adjacent to and in front of the cutter in alignment there-f with and extending from its rigid support in the direction of the advancing fabric far enough to flex freely at its outer end and adapted to engage and slide along a face of the fabric in such row and to bend readily to follow bends in the row and guide the row to the cutter.

5. A slitting machine for cutting a fabric along slightly defined rows, which comprises take-up means for drawing the fabric forward from a source of supply, cutters for cutting the advancing fabric, and means for detecting and following the slightly dened rows comprising flexible detector blades positioned closely adjacent to and in front of each cutter in alignment therewith and adapted to engage and slide along a face of the fabric in such rows and to bend readily at their outer ends with bends in the rows to follow the rows and guide them to the respective cutters.

6 A slitting machine for cutting a fabric along slightly deilned rows, which comprises take-up means for drawing the fabric forward from a source of supply, cutters for cutting the advancing fabric, means for detecting and following the slightly deflned rows comprising exible detector blades positioned closely adjacent to and in front of each cutter in alignment therewith and adapted to engage and slide along a face of the fabric in such rows and to bend readily at their outer ends with bends in thefrows to follow the rows Iand guide the rows to the respective cutters. and means for momentarily moving the cutters out of engagement with Vthe advancing fabric and then back into engagement therewith.

ROBERT J. CLARKSON.

No references cited. 

